Build your vocabulary with fanfic
Promstuck is an illustrated Homestuck fanfic that's longer than many original works, strikingly true to the voices of its huge cast of characters, and genuinely funny (if you already know Homestuck). Every time something reminds me of Promstuck, I have to look up a favorite panel.
But even though Mom Lalonde and Dad Egbert as prom chaperones had stuck with me, I'd forgotten the word diaphoretic, which can mean "inducing perspiration" or "sweating heavily", and is of course used to describe Equius. In fact I'm not sure why else you'd need it.
Last month I read Eliezer Yudkowsky's Harry Potter and the Methods of Rationality, in which budding scientist Harry Potter is sorted into Ravenclaw and alternately transmutes spiderweb into carbon nanotubes and acts insufferable. At one point his invisibility cloak is described as fuliginous, meaning "sooty" or "dusky" (or just "soot-colored"). Not how I pictured the thing, but what a wonderful word!